Atom is composed of various sub atomic particles carrying positive or negative charge as observed and experimented by various scientists. Soon after these sub particles were discovered, scientists became eager to explain the distribution of these charged particles in an atom. It was major challenge before the scientists at the end of the 19th century … Read more
An electron orbital is mathematical function used in describing the wave-like mechanism of either an electron or many pairs of electrons in an atom. This function is later used when in need of providing the probability of locating an atomic electron in a specified area in the nucleus of the atom. Explanation Every orbital is … Read more
The proton was discovered by Ernest Rutherford in 1920 and he was a student of J. J. Thomson. His experiment was based on electrical discharge in the modified cathode ray tubes and it led him to discover the protons. His observations revealed that the particles were charged positively and the rays which carried the positively … Read more
The electron was discovered by J. J. Thomson in 1897, while he was studying the properties of the cathode ray. In 1906 he was awarded a noble prize for the discovery of elemental particle electron. In 1937 he won the noble prize for providing wavelike properties of the electron. In the late of the 19th … Read more
The valence or oxidation state of an element is associated with the electronic configuration and is determined by the electrons present in the valence shell. The number of electrons which an atom loses or gains or shares with another atom to attain the noble gas configuration is defined as its valency. In an ionic compound, … Read more
Chemistry is a branch of science which helps us in study of matter. While studying the matter we basically look at its composition, its properties and how it changes. Anything which has mass and takes up space is called as matter i.e. anything that has physical existence. Chemistry is also sometimes referred as central science … Read more
Substances around us take up some space and have mass. These substances are made up of molecules. Molecules need to be measured in various experiments and here it is necessary that the measurements are accurate. Using calculations scientists determine the number of moles a particular reaction will require. Once the number of moles required are … Read more
The relative tendency of an atom in a molecule to attract the shared pair of electrons towards itself is called electronegativity. The electronegativity of an atom depends on the following factors: Size of the atom: In a smaller atomic shell is placed close to the nucleus. So the nucleus is able to attract bonding electrons … Read more
The molar enthalpy change accompanied by the removal of an electron from an atom or an ion in its ground state is called ionization enthalpy. In general terms, ionization enthalpy represents the energy required to remove one electron from an atom. The ionization enthalpy is expressed in the units of KJ/mol. Since energy is always … Read more
When an electron is added to an isolated gaseous atom or ion in its ground state molar enthalpy change is certain which is called the electron gain enthalpy. Electron Gain Enthalpy is completely different to the Ionization enthalpy. For example, the halogens have highly negative electron gain enthalpy because they cannot obtain a stable noble … Read more